Sulfurized polysulfide materials have been known for some time and have been considered particularly useful for applications such as metal fabricating and gear lubrication. However, it is also known that such materials have an unpleasant odor. Therefore, methods have been developed for reducing or neutralizing this odor when preparing these materials. Alkanolamines have been particularly favored for their odor reducing properties.
Amines are known to counteract the odoriferous effects of sulfurized materials in hydrocarbon materials. The amines can be used as either aqueous or oil-soluble solutions. Alkanolamines may be used for removing, neutralizing, sweetening, or scrubbing hydrocarbon gas streams. Additionally, alkanolamines may be used in conjunction with sulfurized materials, antioxidant, and for stabilizing properties. The combination of sulfurized materials and alkanolamines may be used in water-soluble cutting and grinding fluids.
A number of U.S. and foreign patents have disclosed various methods for using alkanolamines to remove sulfur-containing compounds from hydrocarbon compounds. As an example, U.S. Pat. No. 2,384,146 recognizes generally the problem of odor-causing sulfurized hydrocarbon oils and discloses the use of alkanolamines, specifically 2-amino-2-methyl-propanol, 2-aminobutanol, 2-amino-2-methyl-1,3-propanediol, 2-amino-2-ethyl- 1,3-propanediol, monoethanolamine, diethanolamine, and triethanolamine, to counteract or neutralize odor development. Another example of an amine used to purify a hydrocarbon compound is British Patent 2,167,397 which discloses the selective absorption of hydrogen sulfide from a hydrocarbon gas compound by absorption and regeneration using an alkanolamine absorbent, specifically dimethylethanolamine, ethyldiethanolamine, isopropyldiethanolamine, diisopropylethanolamine, N-ethyldiisopropanolamine, isopropyldiisopropanolamine, and N-methylmorpholine.
Alkanolamines of various types may also be water-soluble and used in aqueous solution. For example, U.S. Pat. No. 4,822,576 discloses the removal of hydrogen sulfide from a gas stream by contacting the stream with an absorbent material such as an amine, or alkanol, etc. or its aqueous solution. The preferred amine is an alkanolamine having one to 10 carbons, especially methyldiethanolamine. U.S. Pat. No. 4,545,965 relates to the selective absorption of hydrogen sulfide from gases containing carbon dioxide using a tertiary amine.
Japanese Patent JP 4139135 relates to the removal of sulfur compounds from hydrocarbon mixtures by treating the compound with N-alkyl alkanolamine and washing with water. U.S. Pat. No. 4,551,158, British Patent 2,167,397, European Patent 190434, and U.S. Pat. No. 4,545,965 disclose similar methods.
U.S. Pat. No. 4,406,868 and U.S. Pat. No. 4,741,884 disclose the removal of hydrogen sulfide from hydrocarbon gases also containing carbon dioxide by alkanolamine absorption and selective stripping.
U.S. Pat. No. 4,551,158 discloses a process in which H.sub.2 S is absorbed from a gas stream using an aqueous alkanolamine solution which is regenerated.
U.S. Pat. Nos. 4,615,818 and 4,690,767, have disclosed the use of hindered amines and an optional acid anhydride or carboxylic acid to form an oil-soluble sulfurized organic composition to reduce the odor of sulfurized organic compounds.
Japanese Patent JP 2113082 discloses water-soluble cutting and grinding fluid compositions which contain an alkanolanfine, an organic sulfur compound, and an aliphatic alcohol.
U.S. Pat. No. 4,086,172 and its continuation-in-part, U.S. Pat. No. 4,170,560, discloses a lubricating oil composition which imparts improved oxidation properties in which sulfurized materials such as aromatic or alkyl sulfides and polysulfides, sulfurized olefins, sulfurized carboxylic acid esters and sulfurized ester olefins act as antioxidants and complex hydroxyalkyl amines act as stabilizers. U.S. Pat. No. 4,089,792 discloses a composition imparting improved oxidation properties in which polysulfides, sulfurized olefins and the like are stabilized by primary and substituted primary amines.
U.S. Pat. No. 4,102,796 discloses a lubricating composition containing a secondary amine in conjunction with aromatic and alkyl sulfides and polysulfides, sulfurized olefins, sulfurized carboxylic acid esters and sulfurized ester olefins. The amine and the sulfurized material composition function together as an antioxidant.
U.S. Pat. No. 4,177,153 demonstrates the use of amines and sulfurized compounds as a stabilizer in a lubricating composition and discloses a lubricating composition containing aromatic or alkyl sulfides, sulfurized olefins and the like in which a tertiary amine acts as a stabilizer. The sulfurized material is acting as an antioxidant and the tertiary amine is acting synergistically to enhance the antioxidant properties.
Although the aforementioned references generally relate to the deodorization and neutralization of sulfurized compounds or the use of amines in combination with sulfurized compounds, they do not relate to the use of an oil-soluble composition comprising a blend of a tertiary alkanolamine and an alkyl alcohol to effectively and efficiently deodorize a polysulfide material. This patent specifically relates to the use of an oil-soluble blend of a tertiary alkanolamine and an alkyl alcohol to effect the deodorization of a polysulfide material.
Accordingly, one object of the present invention is to provide a composition comprising a blend of an alkanolamine and an alkyl alcohol which deodorizes polysulfide materials.